SRD:Teleportation Subschool

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Teleportation

A teleportation spell transports one or more creatures or objects a great distance. The most powerful of these spells can cross planar boundaries. Unlike summoning spells, the transportation is (unless otherwise noted) one-way and not dispellable.

Teleportation is instantaneous travel through the Astral Plane. Anything that blocks astral travel also blocks teleportation.